This invention relates generally to actuating mechanisms, and more particularly, to a sturdy, easily operable and precisely controllable mechanical actuator that may be used in a multitude of situations such as the control of fluid flow, as a latch, as a switch or relay, and the like.
Actuating and latching mechanisms are used in innumerable situations for the mechanical advantages they provide. Generally speaking, an actuator uses a mechanical linkage to initiate some work or actionxe2x80x94stated in another way, to actuate some action. Most latches incorporate a mechanical structure such as an actuator to selectively connect and release adjacent structures, at least one of which is movable relative to the other. Stated in simple terms, the latching mechanism connects the structures to one another to prevent relative movement, and releases the two structures to allow relative movement.
There are just about as many different actuating and latching mechanisms as there are uses for them. Indeed, there are so many different structural designs for these mechanisms that they cannot all be mentioned. But if such mechanisms can be generalized in any reasonable manner, it might be said that they include some kind of mechanical linkagexe2x80x94the actuator linkagexe2x80x94connected to one part of a structure. The actuator is movable between a normally resting position and an actuating position. In the resting position the actuator is typically not initiating or allowing any work. For instance, in the case of a latch, in the resting position the latch is selectively engaged with a cooperative part of an adjacent structure. In the actuating position, the actuator is moved out of the resting position to initiate work. Again referring to a latch, the actuator is moved out of the resting position so that the latch disengages from the adjacent structure so that the structures may move relative to one anther. The actuator is thus movable between a latching position in which the actuator engages the adjacent member and an unlatching position in which the actuator disengages from the adjacent member. In the latched position the two members are usually not movable with respect to one another. The actuator is movable to a second position in which the engagement between the actuator and the second member is disengaged, allowing relative movement of the two members. The actuator is often resiliently biased into one of either the first or second positions (generally the xe2x80x9clatchedxe2x80x9d position), often with some kind of a spring or similar biasing mechanism.
Mechanical latches are ubiquitous and are used in a wide variety of devices. To name just a few of the many hundreds of goods in which latches of various designs are used, they are used in cameras, musical instruments, firearms, engines, cutlery and computers. In other words, a latch may be used in virtually any situation where there is a need to selectively engage and release adjacent structures.
Latches are just one example of the thousands of settings where actuating mechanisms may be used. Another example is in the control of fluid flow. Thus, valves may be classified as actuators since they selectively initiate work; they start and stop the flow of a fluid. A reed valve is a well-known type of fluid control valve that relies upon a mechanical actuator. This kind of a valve uses a valve petal that is attached to a valve casing such that the petal closes a port in the casing. The petal is typically made of a flexible metal and often uses a sealing lip between the petal and the valve casing to ensure a fluid-tight seal around the port. The valve petal is designed to open under fluid pressure moving through the port; when the pressure in the port reaches a predetermined amount, the metallic petal flexes away from the sealing engagement against the valve casing to open the valve and allow fluid flow. When the pressure in the port decreases below the predetermined value, the petal closes into the sealed position.
Reed valves are relatively easily manufactured and inexpensive, and are often beneficially used in two-stroke engines and the like. However, reed valves tend to lack the precision and accuracy that is needed in some fluid flow situations that call for better control.
Despite the many different kinds of actuating mechanisms known in the art, there is a need for still a greater variety of actuating devices that, for example, allow for accurate control of fluid flow and that allow for adjacent structures or parts to be reliably latched or locked and selectively released from the locked position.
The present invention provides an actuating mechanism for use in any situation that calls for a mechanical actuation. Notable among the many situations in which such an actuator may be used are fluid flow control, latches, electrical relays and switches. The inventive mechanism is structurally distinct from the prior art. It is mechanically elegant, strong and reliable, easily operated, versatile and aesthetically attractive.
The actuator is adaptable to virtually any situation where there is a need to initiate mechanically work, for instance to control fluid flow or to interconnect and then release two different members or structures. But the actuator may also be used in many other settings where a mechanical actuator is called for. The practical applications of the present actuator are innumerablexe2x80x94too many to mention.
The actuator is defined by a unitary piece of material that is either an integral part of one structural component or which is connected to one component. In one preferred embodiment, one section of the component defines a panel having a pair of opposed and overlapping, generally U-shaped slots formed therein. The panel is formed of a resilient material and the slots are overlapping such that in combination they define a pivoting lever arm mechanism that is integrally connected with opposite spring arms. When a central section of the panelxe2x80x94that is, the lever armxe2x80x94is pushed in one direction, the opposite, free end of the lever arm moves in the opposite direction. This causes the lever arm to move in a rocking motionxe2x80x94one end of the lever arm moves in one direction while the other end moves in the other direction. This teeter-toter movement may be used to initiate workxe2x80x94that is, to actuate. For example, in the resting position one end of the lever arm may be in a sealing position relative to an adjacent port for containing a fluid. When fluid pressure in the port exceeds a predetermine value, the lever arm moves out of the resting or closed position to open the valve and cause fluid flow through the port. The teeter-toter movement may if desired be used to initiate other work. Thus, since both ends of the lever arm are moving when the actuator is moving, both ends may be used to initiate some secondary work with appropriate linkage.
As another illustration, take the case where a locking pin or some equivalent structure is carried on the lever arm extending toward an adjacent structure such that the locking pin engages the adjacent structure. Since the panel is resilient, the locking pin is normally biased toward the second structure. When the two adjacent structures (that is, the structure that carries the actuator and the adjacent structure that the actuator engages) are in the closed position the locking pin engages a cooperatively formed part and thus latches the two structures to prevent movement relative to one another, locking the two in a first or xe2x80x9clockedxe2x80x9d position. The two structures are unlocked from one another to allow relative movement by actuating the lever arm by pushing one end of the actuator in one direction to pivot or rock the free end of the lever arm and thus move the locking pin out of engagement with the cooperatively formed part of the adjacent structure. The engagement between the locking pin and the adjacent structure is thus released, allowing for relative movement between the two.
Similarly, the invention may be embodied in a system in which an actuator is needed without regard to adjacent, movable structures. The resilient actuator of the present invention may thus be utilized in any situations where a spring-biased actuator is needed.
The lever arm actuating and actuating mechanism may be formed in a variety of different configurations, and the mechanism may optionally be used in combination with a fulcrum positioned between the body that carries the lever arm and the adjacent structure.